[solved] The world physics and tyre physics need "tuning"

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So I tried to set up an online race the same as the BTCC today. Same conditions, same date, same sort of cars. The world model made the track temp to be 54deg Fahrenheit which was pretty spot on because today it was 57deg F at Brands Hatch.

However, when the BTCC and Clio guys were on slicks they were not struggling to get heat in the tyres and suffering with massive oversteer on cold rears like I and everyone else in the online session.

It seems the world physics and tyre physics haven't been properly calibrated. Everyone was seemingly finding the cars undriveable. Not just because we couldn't get heat into the rear tyres but that the tyres would pretty much cool back down to cold in between corners. The problem seems more to be that the two physics models clash.

It also explains the severe un-driveability of the snow career mode races, which I guess takes it even more to the extreme. But given the reality of today's BTCC race and my experiences here, it is not realistic enough to be properly/seriously playable.

Vid of my experiences. (Excuse the driving, I generally just mess around with this game at the moment rather than try to be serious)

 
Actually I'm not sure the above is entirey true. I just tried another FWD touring car and Brands in much warmed conditions by chance in a pubic lobby race and had exact the same problems - rears wouldn't get warm and it was mentally oversteery and twitchy. Everyone else in the race had the same problem.

Maybe this thread needs merging with the "let resolve the oversteer bug" one?
 
So I tried to set up an online race the same as the BTCC today. Same conditions, same date, same sort of cars. The world model made the track temp to be 54deg Fahrenheit which was pretty spot on because today it was 57deg F at Brands Hatch.

However, when the BTCC and Clio guys were on slicks they were not struggling to get heat in the tyres and suffering with massive oversteer on cold rears like I and everyone else in the online session.

It seems the world physics and tyre physics haven't been properly calibrated. Everyone was seemingly finding the cars undriveable. Not just because we couldn't get heat into the rear tyres but that the tyres would pretty much cool back down to cold in between corners. The problem seems more to be that the two physics models clash.

It also explains the severe un-driveability of the snow career mode races, which I guess takes it even more to the extreme. But given the reality of today's BTCC race and my experiences here, it is not realistic enough to be properly/seriously playable.

Vid of my experiences. (Excuse the driving, I generally just mess around with this game at the moment rather than try to be serious)


To claim it's not "realistic enough to be properly/seriously playable", you must know what the rear temperatures are in these cars on a Brands with ambient temps of 54F. Can you please share a link to the data? Also, are you familiar with FF race car handling? Do you know how much weight is on the inside rear wheel when cornering? Here's a couple of hints:
01renaultclio197cup.jpg

ClioCupRacer_03.jpg


Since Brands is mostly right handers, how much heat do you think is building up on the inside right rear when it's carry little to no load during cornering?

I can't say for a certainty that PCAR2 tire temps line up exactly with real world tire temps under these conditions and I'm not making that claim. But intuitively I'd expect any FWD race car that handles in a game like it does in the real world, to have pretty cold rear tires under these conditions and the tire that is inside on the majority of corners is going to be the coldest. Real life drivers won't have an issue with is because they know what adjustments to make on the car to get the rear grip they want and they have enough experience to know how to drive the cars under these conditions.

FWD race cars in general require a different driving technique that FR, MR and RR layouts. Blasting into corners on the brakes or off throttle and turning sharply often results in a tank slapper or a wild slide.
 
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FWD race cars in general require a different driving technique that FR, MR and RR layouts. Blasting into corners on the brakes or off throttle and turning sharply often results in a tank slapper or a wild slide.
Pretty much this. Been driving the Clio Cup just about anywhere without spinning at all. Yes, the rear tyres have less heat in them, yes you will have to work to manage weight transfer a lot more than in other layouts. Nothing wrong there. Throttle is key. Lifting throttle mid-corner is a big no-no.
 
That FF car is kind of throttle-oversteering in the first post's video, which seems unnatural. The car should straighten with the gas when rear looses when driving an FF car, at least in real life.
 
It does in PC2 as well, I've experienced it with both the Clio and Megane TC.
And the FF race cars are much better behaved in PC2 than they were in PC1. If you're used to them in PC1 they're fairly easy to drive in PC2 as they are much easier to catch when going over the limit.
 
That FF car is kind of throttle-oversteering in the first post's video, which seems unnatural. The car should straighten with the gas when rear looses when driving an FF car, at least in real life.
That only holds when you're not actually steering into the corner and/or the front tyres are overloaded. If the fronts still have grip, using throttle while steering into the corner will only pull the car into the corner more.
 
So I tried to set up an online race the same as the BTCC today. Same conditions, same date, same sort of cars. The world model made the track temp to be 54deg Fahrenheit which was pretty spot on because today it was 57deg F at Brands Hatch.

However, when the BTCC and Clio guys were on slicks they were not struggling to get heat in the tyres and suffering with massive oversteer on cold rears like I and everyone else in the online session.

It seems the world physics and tyre physics haven't been properly calibrated. Everyone was seemingly finding the cars undriveable. Not just because we couldn't get heat into the rear tyres but that the tyres would pretty much cool back down to cold in between corners. The problem seems more to be that the two physics models clash.

It also explains the severe un-driveability of the snow career mode races, which I guess takes it even more to the extreme. But given the reality of today's BTCC race and my experiences here, it is not realistic enough to be properly/seriously playable.

Vid of my experiences. (Excuse the driving, I generally just mess around with this game at the moment rather than try to be serious)


There is a technique to driving these cars master it and they are amazing. All about weight transfer and where it’s happening.
 
It all bugged. Nothing sophisticated, It just does not work for many Cars. Also in the official forum has been reported by many users and is deeply affecting career mode.
 


Stop trying to "get heat into the tyres" and just drive a couple of laps at a moderate pace. Stopping every few corners because you spin is not helping your cause.

The rears are never going to be hot and sticky and you're just going to have to deal with it. It's one of the quirks of FF cars, if you've got the same rubber on the front and the back there's only so much you can do to even out the load between the two. Arguably it's intentional in a lot of cars, as it helps get the lift-off oversteer that lets FF cars be really quick.

Sorry, but I see nothing wrong with the physics that some more appropriate driving techniques wouldn't fix. Sometimes you just can't go as fast as you feel like you should be able to. Try just driving to what the car will allow you to do instead of trying to make it fit your expectations. I'm guessing you're not a BTCC or Clio Cup driver in real life, so expecting to be able to replicate exactly what they're able to do is probably giving yourself a bit much credit.
 
So I tried to set up an online race the same as the BTCC today. Same conditions, same date, same sort of cars. The world model made the track temp to be 54deg Fahrenheit which was pretty spot on because today it was 57deg F at Brands Hatch.

However, when the BTCC and Clio guys were on slicks they were not struggling to get heat in the tyres and suffering with massive oversteer on cold rears like I and everyone else in the online session.

It seems the world physics and tyre physics haven't been properly calibrated. Everyone was seemingly finding the cars undriveable. Not just because we couldn't get heat into the rear tyres but that the tyres would pretty much cool back down to cold in between corners. The problem seems more to be that the two physics models clash.

It also explains the severe un-driveability of the snow career mode races, which I guess takes it even more to the extreme. But given the reality of today's BTCC race and my experiences here, it is not realistic enough to be properly/seriously playable.

Vid of my experiences. (Excuse the driving, I generally just mess around with this game at the moment rather than try to be serious)



I’ll also give you a tip.

There are other ways of generating heat for the rear tyres than simply reducing the pressures to their minimum. My tyre pressures for the same car at Sugo are 1.57 bar. What PCars2 does well, and in my opinion its what a lot of folk are struggling with, each car has its own working window, for tuning and how you drive it.
 
While issues do exist with the tyre temps in some cars in PC2 it does need to be remembered that these are not 'easy' cars to master in reality, the Clio's in particular.

Its a car with a short wheelbase, relatively high centre of gravity and a rear that's set-up to be very loose.

A quick look at the start of this Clio Cup race at Brands Hatch GP illustrates this rather well, the slightest contact or late brake can see the rear step out, and constant quick steering correction is needed in a lot of the corners.



Watch from 1:19 as playback from outside youtube has been disabled.
 
My biggest tip (and the hardest thing for me to remember when changing from RWD to FWD) for lessening the snap oversteer is to keep it in the lowest gear possible when cornering and keeping the revs high, even changing down mid corner to keep the front wheels rotating as fast as possible to keep it in line, I spend more time on RWD cars and do tend to do the opposite by reflex.
 
While issues do exist with the tyre temps in some cars in PC2 it does need to be remembered that these are not 'easy' cars to master in reality, the Clio's in particular.

Its a car with a short wheelbase, relatively high centre of gravity and a rear that's set-up to be very loose.

A quick look at the start of this Clio Cup race at Brands Hatch GP illustrates this rather well, the slightest contact or late brake can see the rear step out, and constant quick steering correction is needed in a lot of the corners.



Watch from 1:19 as playback from outside youtube has been disabled.


Yes. But in the game the biggest issue that makes the car unstable is surely the tyres issue. Hope they fix It ASAP so we can experience how accurate is the physic for this car. Right now everthing is offset by tyres temps.
 
Yes. But in the game the biggest issue that makes the car unstable is surely the tyres issue. Hope they fix It ASAP so we can experience how accurate is the physic for this car. Right now everthing is offset by tyres temps.
The simple answer to that is that we don't know.
 
No it was a
I’ll also give you a tip.

There are other ways of generating heat for the rear tyres than simply reducing the pressures to their minimum. My tyre pressures for the same car at Sugo are 1.57 bar. What PCars2 does well, and in my opinion its what a lot of folk are struggling with, each car has its own working window, for tuning and how you drive it.

If you look at the start, the tyres are set to the lowest pressure possible and I even closed off the rear brake ducts.

Anyway, this is definitely a bug I think to do with the steering sensitivity rather than pure tyre temps because I just deleted all my settings and setups and had another go in the exact same conditions and it was easier to control even on stone cold tyres. The but grass and kerbs are still deadly to the rears - acting more like a high powered rwd car of full throttle.

It seems if you put a tiny bit too much steering input in it acts like it locks the wheels fully over or something, which it then slides and the physics model then goes out of know parameters and throws a benny. Fwd cars are simply not this unstable. I've driven many in anger. I'm also not convinced the tyre model is correct. I've raced karts in 5deg C temps and I guarantee you, 1 lap or so and the tyres are easily hot enough to burn your hands...
 
No it was a


If you look at the start, the tyres are set to the lowest pressure possible and I even closed off the rear brake ducts.

Anyway, this is definitely a bug I think to do with the steering sensitivity rather than pure tyre temps because I just deleted all my settings and setups and had another go in the exact same conditions and it was easier to control even on stone cold tyres. The but grass and kerbs are still deadly to the rears - acting more like a high powered rwd car of full throttle.

It seems if you put a tiny bit too much steering input in it acts like it locks the wheels fully over or something, which it then slides and the physics model then goes out of know parameters and throws a benny. Fwd cars are simply not this unstable. I've driven many in anger. I'm also not convinced the tyre model is correct. I've raced karts in 5deg C temps and I guarantee you, 1 lap or so and the tyres are easily hot enough to burn your hands...
I currently recording a video to show you otherwise in my opinion, reducing tyre pressures is not the only way.
 
youtu.be/7hodx568fhs?t=107

I think i could actually race a Clio in real life as Knapp there does exactly what i do in these Clio's!
 
I've raced karts in 5deg C temps and I guarantee you, 1 lap or so and the tyres are easily hot enough to burn your hands...
I just did a few laps in the Clio: offline race, 25 minutes qualy, winter, heavy clouds. Ambient temp 6 degrees C. During qualy my fronts went up to 80-85 degrees C. Rears up to 58-60-ish. Car was easy to drive, easy to catch. Same for the Mégane. The only difference between the two of us is setup and driver. Could be the driver, but I'm not ruling out the setup bug either. Personally, I don't bother with custom setups until I get a hang of the car.

What's the fastest lap you can do with either the Clio or the Meg without crashing?

youtu.be/7hodx568fhs?t=107

I think i could actually race a Clio in real life as Knapp there does exactly what i do in these Clio's!
It's funny that in the beginning of that vid there's a spun-out car every other corner. :lol: It also shows clearly where and how he brakes and how he approaches the corners and when he puts the throttle on. 👍

The ghosts for the top times in these cars in time trial are also worth investigating.
 
So I tried to set up an online race the same as the BTCC today. Same conditions, same date, same sort of cars. The world model made the track temp to be 54deg Fahrenheit which was pretty spot on because today it was 57deg F at Brands Hatch.

However, when the BTCC and Clio guys were on slicks they were not struggling to get heat in the tyres and suffering with massive oversteer on cold rears like I and everyone else in the online session.

It seems the world physics and tyre physics haven't been properly calibrated. Everyone was seemingly finding the cars undriveable. Not just because we couldn't get heat into the rear tyres but that the tyres would pretty much cool back down to cold in between corners. The problem seems more to be that the two physics models clash.

It also explains the severe un-driveability of the snow career mode races, which I guess takes it even more to the extreme. But given the reality of today's BTCC race and my experiences here, it is not realistic enough to be properly/seriously playable.

Vid of my experiences. (Excuse the driving, I generally just mess around with this game at the moment rather than try to be serious)


Ok just realised I cant get telemetry up from a replay file :ouch:

Can you provide me with room settings so I can have a go at replicating what you experienced with a different result?
 
I just did a few laps in the Clio: offline race, 25 minutes qualy, winter, heavy clouds. Ambient temp 6 degrees C. During qualy my fronts went up to 80-85 degrees C. Rears up to 58-60-ish. Car was easy to drive, easy to catch. Same for the Mégane. The only difference between the two of us is setup and driver. Could be the driver, but I'm not ruling out the setup bug either. Personally, I don't bother with custom setups until I get a hang of the car.

What's the fastest lap you can do with either the Clio or the Meg without crashing?

Not tried the clio after hearing other people were having similar issues. I think the later race at brands I was doing low 1:34s/ high 1:33s IIRC. But there was still major oversteer problems with the steering input and in a 20 lap race I don't think I ever got the rear temps beyond 135deg F. Similar times and same issues with a guy I used to race a league with. We both spun several times, usually by putting about 1/4 of a rear wheel on the grass. IT would whip round like a 1000bhp rwd monster.

Ok just realised I cant get telemetry up from a replay file :ouch:

Can you provide me with room settings so I can have a go at replicating what you experienced with a different result?

Room settings? You mean for the track conditions? Set date as1/10/17 at about 14:00 as the date and overcast to light rain (never got to the point of rain). Track temp was 54deg F.
 
I think the later race at brands I was doing low 1:34s/ high 1:33s IIRC.
That doesn't sound too bad to me? Top in TT is a 1:32.246 right now. And spinning when hitting the grass with a rear is pretty common too. I'm really not sure there's a problem to be honest. Your rears seem to be a bit lower than mine, but other than that I think you're good. Those times are not too far off real life lap records either (http://www.btcc.net/calendar/brands-hatch-gp/). :)
 


The similarity to racing online is uncanny. First corner pile up, and half the field has spun at least once in the first lap. :P

Fwd cars are simply not this unstable. I've driven many in anger.

There's a difference between road cars and race cars. Road cars are purposely set up to be forgiving and not snap at the driver when they push beyond the limit. Race cars are the opposite: they are set up to be nimble and rely on the driver having the skill to control it when it all goes pear shaped.

You can't look at Scaff's video and tell me that those cars are anything like a road-going Clio. If that were so, the car would have been recalled in the first week after killing it's first thousand drivers.

We both spun several times, usually by putting about 1/4 of a rear wheel on the grass. IT would whip round like a 1000bhp rwd monster.

The outside wheel? The one that has the entire weight of the rear on it because the other tyre is off the ground?

Yep. That's how it's supposed to work. I suggest not putting your wheels on the grass.
 
I've just taken a stock Clio around Brands Indy, driving it as a fwd race car should be (max out the revs when cornering and don't lift without expecting it to need a catch) and it's fine.

Silly degrees of fun actually.

I will post a video up later.
 
There's a difference between road cars and race cars. Road cars are purposely set up to be forgiving and not snap at the driver when they push beyond the limit. Race cars are the opposite: they are set up to be nimble and rely on the driver having the skill to control it when it all goes pear shaped.
This is perfectly demonstratable in the game: just pick the Mégane RS road car and throw it around the track. After having driving the Cup Clio or Mégane TC it will feel like it's on rails, almost impossible to crash unless you really, really overdo it. 👍

I've just taken a stock Clio around Brands Indy, driving it as a fwd race car should be (max out the revs when cornering and don't lift without expecting it to need a catch) and it's fine.
I managed a low 1:33 on Brands Hatch GP with the Mégane in winter conditions, 1:32.288 in TT. Should be plenty of more in there for more capable drivers too. 👍
 
Also, are you familiar with FF race car handling? Do you know how much weight is on the inside rear wheel when cornering? Here's a couple of hints:
01renaultclio197cup.jpg

ClioCupRacer_03.jpg

The reason the inside wheel is lifting is a direct result of the high level of grip being generated by the outside tyre. All those pics prove @mattikake 's point the Clio Cup doesn't have the same level of rear end grip in the game.

I have to admit that I didn't yet buy PCars 2 so I can't personally comment directly about the car drives in that game. However, I remembered how loose the rear and of the Clio Cup was in PCars1 so I just fried it up again and ran a few laps around Brands Hatch to remind me exactly what I was dealing with and I came to the same conclusion. Driving that Clio should not be about managing a loose rear end, particularly at relatively low speeds. If anything should be managed it should be understeer and I believe being over aggressive on the throttle during cornering is the last thing that should be done.

I do own and have tracked a Renaultsport Clio on semi-slick tyres so I have a modicum of experience of how these cars behave but the racer takes the grip levels to a higher degree as can be seen here:

 
The reason the inside wheel is lifting is a direct result of the high level of grip being generated by the outside tyre. All those pics prove @mattikake 's point the Clio Cup doesn't have the same level of rear end grip in the game.

I have to admit that I didn't yet buy PCars 2 so I can't personally comment directly about the car drives in that game. However, I remembered how loose the rear and of the Clio Cup was in PCars1 so I just fried it up again and ran a few laps around Brands Hatch to remind me exactly what I was dealing with and I came to the same conclusion. Driving that Clio should not be about managing a loose rear end, particularly at relatively low speeds. If anything should be managed it should be understeer and I believe being over aggressive on the throttle during cornering is the last thing that should be done.

I do own and have tracked a Renaultsport Clio on semi-slick tyres so I have a modicum of experience of how these cars behave but the racer takes the grip levels to a higher degree as can be seen here:


Respectfully, based on your response above, you have a great deal to learn about front wheel drive race cars and how they handle in the real world.
 
I have to admit that I didn't yet buy PCars 2 so I can't personally comment directly about the car drives in that game. However, I remembered how loose the rear and of the Clio Cup was in PCars1 so I just fried it up again and ran a few laps around Brands Hatch to remind me exactly what I was dealing with and I came to the same conclusion.
The Clio Cup in PC1 is not the same as in PC2. In PC1 it's much harder to handle than in PC2. As already pointed out by people that drove it, like a lot, and are on/near the top of the leaderboards. See also the videos of actual Clio Cup races above, snap oversteer galore. This car only kills when not driving it properly (the onboard IRL race video a few posts up demonstrates this).

Driving that Clio should not be about managing a loose rear end, particularly at relatively low speeds. If anything should be managed it should be understeer and I believe being over aggressive on the throttle during cornering is the last thing that should be done.
Doesn't that race vid show exactly what you're saying shouldn't happen?
 
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